Can high volume plasmapheresis be performed with bedside dialysis machines and if so, how often should the dialyser/filter be changed?

High Volume Plasmapheresis Using Bedside Dialysis Machines

High volume plasmapheresis can be performed with bedside dialysis machines, but the filter/dialyzer should be changed after each treatment session to maintain optimal efficiency and prevent complications. 1

Technical Considerations for High Volume Plasmapheresis

Equipment Requirements

• Standard bedside dialysis machines can be adapted for plasmapheresis, particularly when using membrane plasma filtration techniques rather than centrifugation methods 2
• The procedure requires specialized filters with appropriate pore size to allow plasma separation while retaining cellular blood components 2
• Proper blood warming equipment should be used, especially for high volume procedures, to prevent hypothermia and associated complications 1

Filter/Dialyzer Management

• For high volume plasmapheresis (typically defined as exchanges >5L), the filter/dialyzer should be changed after each treatment session 1
• Reusing filters for multiple high-volume sessions increases risks of:
  • Reduced filtration efficiency due to protein coating of the membrane 3
  • Higher risk of hemolysis, which occurs in up to 20% of patients undergoing double-filtration plasmapheresis 4
  • Increased risk of thrombotic complications within the circuit 3

Vascular Access Considerations

• Peripheral venous access is preferred initially for plasmapheresis procedures 1
• For high volume procedures, adequate blood flow rates (typically >100 mL/min) are essential, which may require larger gauge catheters 3
• Arteriovenous fistulas may be needed if peripheral access becomes impossible, but central venous catheters should be avoided except in emergencies 1

Procedural Protocol for High Volume Plasmapheresis

Treatment Parameters

• For conditions requiring high volume exchange (such as ANCA vasculitis with pulmonary hemorrhage):
  • Initial volume replacement should be calculated at 60 mL/kg 1
  • Treatment frequency: daily until clinical improvement (e.g., bleeding stops), then every other day 1
  • Total course typically consists of 7-10 treatments 1

Filter Change Protocol

• The dialyzer/filter should be changed:
  • After each complete treatment session 1
  • If signs of filter clotting or decreased efficiency occur during treatment 3
  • If treatment is interrupted for more than 30 minutes 1

Monitoring Requirements

• Continuous patient monitoring is essential during high volume procedures to detect complications early 3
• Key parameters to monitor include:
  • Hemodynamic stability (blood pressure, heart rate) 3
  • Filter pressure readings to detect early clotting 1
  • Signs of adverse reactions (paresthesias, chills, hypotension) 3

Complications and Management

Common Complications

• Hypotension (occurs in 8.4% of procedures) - manage with fluid boluses and temporarily reducing exchange rate 3
• Arrhythmias (3.5% of procedures) - require continuous cardiac monitoring during treatment 3
• Paresthesias and temperature sensations (1.1%) - typically transient and mild 3

Severe Complications

• Life-threatening complications occur in approximately 2.16% of procedures, including:
  • Severe hypotension requiring vasopressors 3
  • Persistent arrhythmias 3
  • Hemolysis 3, 4

Special Considerations for High Volume Exchange

• For exchanges >5 liters, albumin replacement is recommended at a dose of 8g albumin per liter of plasma removed 1
• The procedure should be completed in a single session rather than multiple smaller volume exchanges to reduce complication risks 1
• Anticoagulation protocols may need adjustment for high volume procedures to prevent circuit thrombosis while minimizing bleeding risk 1

Practical Implementation Tips

• Ensure the dialysis machine is properly calibrated for plasmapheresis mode before initiating treatment 1
• Use ultrasound guidance for vascular access when available to reduce adverse events 1
• Complete the entire high volume exchange in a single session (typically 1-4 hours) rather than extending over multiple days 1
• Always have replacement fluids warmed to body temperature before administration 1